Alveolar bone height correlates well with subsequent tooth loss. In research settings, manual measurements of bone height from digitized images of radiographs have shown a precision of about 0.5 mm which can be improved further by using image processing and registration techniques. Based on these data, we believe that bone height change can be measured reliably from dental radiographs and that dental care would improve if these measurements were brought into the dental office. But translation of these techniques will require a "system" which is well-suited to the normal work flow of the dental office. The goal of this proposal is the development and implementation of a reliable, sensitive, easy to use, rapid system for measurement of alveolar bone height change which will be accepted and desired in the general practitioner's office. Simply stated, our goal is to develop the system that general practitioners will want and that they will view as an essential part of their patient care capabilities. To achieve this goal, we are proposing innovative approaches to address issues which have obstructed translation of crest height measurements in oral radiographs into general dental practice. (1) For single radiographs, we will use manual indication of the cemento-enamel junction (CEJ) and crest-tooth junction, but we will use image analysis to refine and improve the accuracy of these indications, thereby also removing the onus of careful placement of points. (2) When two or more radiographs are compared for assessment of bone height change, (a) we will automatically register the CEJ and crest-tooth junctions in the radiographs to further improve the accuracy of the change measurements and (b) we will automatically determine and correct for jaw angulation. (3) We will package these techniques in a simple, easy to use, and quick graphical user interface. Our ultimate goal (after completion of Phase 2) is to perform automated full-mouth (64 sites) analysis based on the methodology developed in Phase 1 (for a single site) in less than one minute per patient. All past methods for measuring bone height are not simple, accurate, and rapid enough for use in the dental office;our proposed product meets these criteria. This complete system, prototyped in Phase 1 and completed in Phase 2, will provide the general practitioner with the means to assess bone height change for every patient, for each site, in an easy and rapid manner. As a result, diagnosis of destructive periodontal disease will be available without negative effects on normal clinical work flow or patient comfort. This system will result in a new first line of defense in the diagnosis and treatment of destructive periodontal disease, giving the general practitioner the ability to detect and treat the disease at an earlier stage. Thus, we expect our system to be adapted easily into dental practice and achieve strong market penetration, which (coupled with accurate, precise, and reliable data) means improved dental care for millions of patients. PUBLIC HEALTH RELEVANCE: Alveolar bone height correlates well with subsequent tooth loss. The goal of this proposal is the development and implementation of a reliable, sensitive, easy to use, rapid system for measurement of alveolar bone height change for the general practitioner's office. This system will consist of methods for measurement of crest height in single images, measurement of crest height change in two or more images, and a simple, easy to use, software interface. This complete system will provide the general practitioner with the means to assess bone height change for every patient, for each site, in a rapid manner. This system will result in a new first line of defense in the diagnosis of periodontal disease and its activity that has the ability to monitor all patients who visit the dental office, thus giving the general practitioner the ability to detect and treat the disease at an earlier stage.